Congress has passed a four-year reauthorization of Federal Aviation Administration programs, marking the end of a series of short-term extensions dating back to 2007. The bill, which won final approval from the Senate late Monday on a 75-20 vote, now goes to President Obama.

The measure runs through fiscal 2015 and authorizes almost $16 billon annually for the FAA, including funding for the next-generation air traffic control system, according to Senate Commerce Committee Chairman Jay Rockefeller, D-W.Va. The legislation also:

• Mandates improved navigational procedures at the nation's top 35 airports to reduce congestion and delays.

"We're obviously very happy that the bill passed," said Doug Church, a spokesman for the National Air Traffic Controllers Association, which represents some 20,000 FAA workers. The bill restores employees collective bargaining rights, he said, after the agency in 2006 "unilaterally" imposed pay cuts and changes in working conditions.

The newly passed bill is the first long-term FAA reauthorization measure since 2007. In the interim, lawmakers had resorted to 23 extensions, the latest of which expires Feb. 17. The House passed the measure on Friday.

The legislation also preserves Essential Air Service, a program that subsidizes air travel to small and medium-sized communities, and lets stand a 2010 National Mediation Board decision making it easier in some respects for airline and railroad workers to unionize. A congressional standoff over that decision helped prompt a partial shutdown of the FAA last summer that furloughed more than 3,700 employees and halted numerous construction projects for about two weeks.

The legislation also makes it harder for airline employees to vote for a union. The legislation requires that 50 percent of employees in a potential bargaining unit vote yes to hold a union election. The previous threshold was 35 percent.